As a hoopster, Kaepernick scored 34 points in a state tournament playoff game. Baseball? He threw 92 miles per hour and was drafted by the Chicago Cubs. But he really loved football. So he went to the University of Nevada, where he ran the “Pistol Formation” and starred for the Wolf Pack of the Western Athletic Conference.

Kaepernick was a second-round draft pick (36th overall) in 2011 and didn’t start a game in the NFL until last Nov. 19. He has started only nine games.

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Sunday night, he will call the shots for the favored San Francisco 49ers against the Baltimore Ravens in Super Bowl XLVII.

This makes him the rarest of rare — a Super Bowl quarterback who is a big mystery to most of mainstream America. A young man of mixed racial background, Kaepernick was adopted by parents in Milwaukee, moved with his family to Turlock, Calif., when he was 4 years old, and has always impressed coaches and fans with his speed and athleticism. He runs a 4.53 40 and throws a football more than 60 miles per hour.

He also has more tattoos than Dennis Rodman. Most of his body art is taken from the Bible.

Kaepernick’s baseball ability interests me most. With so few football offers on the table, it must have been tempting to sign with the Cubs out of high school.

Jeff Haynes/REUTERS

A look at one of Kaepernick’s tattooed arms.

When did he choose?

“I chose football as soon as I had the option for football.’’

What about the third sport. Was basketball ever a possibility?

“No.’’

Was there any sport that you had trouble with? Which one was the hardest for you?

“I don’t know. I played football, baseball, and basketball my whole life. It’s just what I was used to.’’

If I went up to hit against you, what would you throw? How would you start me off?

“It depends on how you set up in the batter’s box. What kind of stance you have. How close you’re standing.’’

I’m going to have a closed stance, leaning toward the plate a little bit.

“First one’s coming at your chin.’’

Ouch.

Again.

This 25-year-old man is NFL Future. He is 6 feet 4 inches, weighs 230, and is ripped. Freezing defenders, running the trendy “Read Option,” Kaepernick can sling it and he can beat you with his legs.

He rushed for 181 yards in the Niners’ playoff win against the Green Bay Packers.

San Francisco coach Jim Harbaugh’s bold decision to replace starter Alex Smith (Smith took the Niners to the NFC Championship game last year) goes down as one of the great moves in the history of sports.

This wasn’t like going with Tom Brady after Drew Bledsoe got hurt. This was a conscious choice to go with a guy with a higher ceiling.

Kaepernick is not a verbal guy. Wearing his oversized Niners cap in flat-bill, rapper style, he looks like a kid you’d find in a skateboard park. He is humble, polite, and not given to public introspection.

Here’s the Niners’ QB on:

Preparing for the Super Bowl: “It’s another game. You have to go out and execute.’’

Dreaming about playing in the Super Bowl as a child: “That was a dream as a kid and things worked out.’’

What he attributes most of his success to: “It’s been a long path to get here. A lot of it is hard work and great coaches. Good guidance along the way.’’

Replacing Smith: “It’s a competitive situation. The NFL is a business and you have to take advantage of the opportunity when you have it. Alex is a great guy. I have nothing but great things to say about him, but at the same time you have to try and do what’s best for you.’’

He demonstrated some sympathy for other adopted kids, particularly those who might not look much like their parents or siblings.

“When my family would check into a hotel, it seemed like there was always someone asking me if I needed help,’’ Kaepernick recalled. “And my parents would be right there standing beside me.’’

He didn’t share many other inner feelings. Kaepernick is not Ray Lewis or Curt Schilling. He doesn’t say much about himself. But this week we have learned that he was adopted when he was six weeks old. His biological father is African-American. He got his first tattoo when he was 19. His favorite tat is the one inside his biceps that reads, “My gift is my curse.’’ He watched Reggie White when he was a kid. He reads the Bible every day. He does not watch sports on television. His favorite TV show is “The First 48.’’

And by late Sunday night, he might be one of the most famous athletes in the world.

***

Backups who went on to become Super Bowl QBs in same season

Colin Kaepernick is not the first quarterback to take over as a starter during the regular season and lead his team to the Super Bowl. Tom Brady replaced Drew Bledsoe, who was injured in Week 2, in 2001. Here are some notable examples of a backup reaching the title game after sitting out his team’s first five games of the season (Brady started Week 3). Four of the five went on to win the championship.

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